perf: Optimize folder UpdateTime timestamp by using int64 instead of time.Time

internal/storage/fake/bucket.go

@@ -271,7 +271,7 @@ func (b *bucket) mintObject(
 func (b *bucket) mintFolder(folderName string) (f gcs.Folder) {
 	f = gcs.Folder{
 		Name:       folderName,
-		UpdateTime: b.clock.Now(),
+		UpdateTime: b.clock.Now().UnixNano(),
 	}
 
 	return
@@ -1224,7 +1224,7 @@ func (b *bucket) RenameFolder(ctx context.Context, folderName string, destinatio
 	for i := range b.folders {
 		if strings.HasPrefix(b.folders[i].Name, folderName) {
 			b.folders[i].Name = strings.Replace(b.folders[i].Name, folderName, destinationFolderId, 1)
-			b.folders[i].UpdateTime = time.Now()
+			b.folders[i].UpdateTime = time.Now().UnixNano()
 		}
 	}
 
@@ -1245,7 +1245,7 @@ func (b *bucket) RenameFolder(ctx context.Context, folderName string, destinatio
 	// Return the updated folder.
 	folder := &gcs.Folder{
 		Name:       destinationFolderId,
-		UpdateTime: time.Now(),
+		UpdateTime: time.Now().UnixNano(),
 	}
 
 	return folder, nil

internal/storage/gcs/folder.go

@@ -16,21 +16,25 @@ package gcs
 
 import (
 	"strings"
-	"time"
 
 	"cloud.google.com/go/storage/control/apiv2/controlpb"
 )
 
 type Folder struct {
 	Name       string
-	UpdateTime time.Time
+	UpdateTime int64
 }
 
 func GCSFolder(bucketName string, attrs *controlpb.Folder) *Folder {
 	// Setting the parameters in Folder and doing conversions as necessary.
+	var updateTime int64
+	t := attrs.GetUpdateTime().AsTime()
+	if !t.IsZero() {
+		updateTime = t.UnixNano()
+	}
 	return &Folder{
 		Name:       getFolderName(bucketName, attrs.Name),
-		UpdateTime: attrs.GetUpdateTime().AsTime(),
+		UpdateTime: updateTime,
 	}
 }
 

internal/storage/gcs/folder_test.go

@@ -48,5 +48,23 @@ func TestGCSFolder(t *testing.T) {
 	gcsFolder := GCSFolder(TestBucketName, &attrs)
 
 	assert.Equal(t, attrs.Name, gcsFolder.Name)
-	assert.Equal(t, attrs.UpdateTime.AsTime(), gcsFolder.UpdateTime)
+	assert.Equal(t, attrs.UpdateTime.AsTime().UnixNano(), gcsFolder.UpdateTime)
+}
+func BenchmarkGCSFolder(b *testing.B) {
+	timestamp := &timestamppb.Timestamp{
+		Seconds: 1234567890,
+	}
+	attrs := controlpb.Folder{
+		Name:       "projects/_/buckets/testBucket/folders/testFolder",
+		UpdateTime: timestamp,
+	}
+
+	b.ReportAllocs()
+	b.ResetTimer()
+	for b.Loop() {
+		// this triggers 2 allocations
+		// the string creation inside getFolderName()
+		// and the &Folder{} heap allocation
+		_ = GCSFolder("testBucket", &attrs)
+	}
 }